Scraping device



June 11, 1940. -i c. oT s 2,203,966

SCRAPING DEVICE Filed lay 16, 1938 v 4 Sheets-Sheet 1 In In noted June 1UNITED- STATES azosm a g r 1 smenavros Herbert 0. our, Dallas, Tex.Application May 16, ms, Serial- No. 208,323

11 Claims.

. This invention relates to new and useful improvements inscrapingdevices.

One object ofthe invention is to provide an improved device which isparticularly adapted for use in removing paramn, or other accumulationfrom the wall oi the bore of well tubing. or other pipe. 7

An important object of the invention is to provide an improved scrapingdevice for removing so that the scraping members thereof arecircumi'erentiaily retractible, whereby the outside diameter of thescraper formed by said members may be reduced to; permit lowering of thedevice through a tubing bore having a coating of parafin therein,without said members scraping or removing the paraifin during suchlowering; the

members being automatically expanded on the or accumulation of para onsaid wall may be accomplished.

Another object of the invention is to provide an improved scrapingdevice including a support having arcuate scraping members mountedthereon, said members being constructed so as to (meet with each otherand the support, whereby the members are rigidly sustained in scrapingposition and .the load imposed thereon is carried by the support, ratherthan by the members alone.

A further object of the invention is to provide an improved parafllnremoving device including a tapered support having radially movablescraping elements mounted to slide vertically thereon, whereby when theblades move verticaly with relation to the support they are expanded orretracted radially so as to vary the diameter of the-scraper formed bythe blades;

A still further object of the invention is to provide a scraping deviceof the character described which may be run into or removed from parafrom well tubing which-is constructed I constructed in accorce with theinvention and showing thescraper members in a retrac position,

Figure 2 is a silar view witnthe scraping members expanded into scrapingposition,

Figure 3 is a view similar to Figure 2 and viewed at right angles to thelatter,

Figure 4: is a horizontal, cross-sectional view taken on the line i-t ofe, 2,

Figure 5 is a horinontal, cross-sectional view taken on the line H ofFigure 2,

Figure 6 is a hontal, cross-sectional taken on the line 6-6 or t o 2, lFl 7 is a horizontal, crcss-sectiol view taken on the l-l oi 2,

figure a is an isometric view or the scraper assembly,

Figure 9 is an isometric view of M2; of the sleeve or body which carriesthe scraper members, and showing the walls thereof in sec tions,

Figure ill is an isometric view or two oi the scraper members,

Figure ii is a transverse, vertical, sectional view taken through thesupporting sleeve or body,

Figure i2 is a tramverse, vertical, sectional view talren on the lineiii-ii of Figure 11,

, Figure 113 is a horizontal, cross-sectional view taken on the lineld-itl of Figure 11,

Figure 14 is a transverse, vertical, sectional new or a modified form ofthe invention, with the scraping members in a retracted sition, Figure15 is a view, ly in elevation and partly in section, of this form oi theinvention with the scraping members in an expanded or scraping position,

Figure 16 is aview similar to ri5 and showing the device viewed at aright angle with respect to Figure 15, A

Figure 17 is a horizontal, cross-sectional view taken on the linel'l-l'l of Figure 15,

Figure 18 is a horizontal, cross-sectional view taken on the llne'W-IOof Figure 15,

Figure 19 is a view, partly in elevation and partly in sectiomof anotherterm of the invention, with the scraping members retracted,

Figure 20 is a similar view, with the scraping members expanded intoscraping position,

view

lit

' ing A, or other tubular member.

ly in section, of still another form of the invention,

Figure 23 is a horizontal, cross-sectional view taken on the line 2323of Figure 22, and

Figure 24 is a plan view of one of the scraping members shown .in Figure22.

In the drawings, 'the numeral ||l designates an elongate support, ormandrel which has its upperportion substantially cylindrical incrosssection. Below the cylindrical portion, the outer surface of themandrel is flared or inclined outwardly, as shown at H, and an enlargedflange I2 is preferably made integral with the lower end of the mandrel.The provision of the collar forms an external, annular shoulder I2 atthe base of the flared or inclined surface I of said mandrel. The lowerend of the collar l2 may be bevelled at its outer peripheral edge tofacilitate lowering of the mandrel through a well tub- The upper endofthe mandrel I is externally screw-threaded to receive a cap member, orhead, I4 which has an external flange. l5 at its upper end. Theunderside of the flange is recessed or undercut at i6, whereby asuitable tool (not shown) for raising or lowering the mandrel throughthe tubing may be engaged therewith,

as will be explained.

,A scraper assembly B is slidably mounted on the mandrel l0, beingconfined between the head 7 l4 and the collar l2. The assembly includesan annular body or sleeve H which surrounds the mandrel and is slidablevertically thereon. A pair of upper scraper members I! and a pair oflower scraper members I! are carried by the body or sleeve and themembers have their inner surfaces engaging the outer surface of themandrel l0, whereby as the sleeve l1 and blades move downwardly of themandrel, their lower ends are moved outwardly by the inclined surface llof a said mandrel; upward movement of the sleeve and members permitsinward movement of said members to a retracted position (Figure 1).

For mounting the scraper members It and M9 in the sleeve or body H, thebore ll of said sleeve is formed'with an internal, annular recess 20which is located near the upper endof said bore (Figure 9). A pair ofdiametrically opposed vertical groovesor channels 2|, are formed in thewall of the bore l1 and extend downwardly from the recess 20 to thelower end of the sleeve and these grooves are adapted to receive theupper scraper members IS. The lower portion of the sleeve is reduced toform an annular skirt 22 and an arcuate notch 2|, which has awidthgreater than the width of the grooves 2|, is-provided in the skirtadjacent each groove.

' Each upper scraper membercolnprises a T- shaped shank or arm which isformed with an arcuate cutting blade l8 at its lower end, preferablymade integral therewith. The lateral arms Ila. of the shank are arrangedto be inserted within the'annular recess 20 and when so inserted, thescraper member is suspended from the shoulder 20' formed by the recess,with the shank I8 extending through the vertical channel 2| and thecutting blade l8 disposed within the notch 2| at the lower end of thesleeve H. The transverse width of the blade is greater than the combinedwidth of the shank and the wall of the sleeve whereby the outer surfaceof the blade projects beyond the outer surface of the by gravity; or

sleeve l'l when the shank is engaging the bottom of the groove. orchannel 2|, as shown in Figure 2.

With the above arrangement, the upper scraper members l8 are suspendedfrom the annular recess 20 and may undergo a limited lateral movement.Displacement of the members is prevented by the outer surface of themandrel III which is adjacent the inner vertical surfaces of the shanksof the members. When the members l8 are in position within the sleeve,the bottom of each cutting blade I. is substantially flush with thelower edge of the skirt 22.

The lower scraper members l9 are located between the lower members IS,whereby the four members are preferably equally spaced around thesleeve. The lower members are constructed in substantially the samemanner as the upper members, except that the shank of each is elongatedso as to position the cutting bladesl! below the lower end of the skirt22 of the sleeve H. The lower members ii are suspended from the annularrecess 20 in the same manner as With sucharrange- IQ of the lowermembers l9, are of such length as to extend through an are greater thanninety degrees, whereby the ends of said blades overlap I each other(Figure 6). This overlapping is possible because the blades I! aredisposed in a horizontal plane below the blades l8 (Figures 1 to 3-) andit is preferable that the upper surfaces of the lower blades l9" engagethe under- Q side of the overlapping ends of' the upper blades l8,whereby a continuous circumferential scraper is formed by the blades.

In using the device,-the same may be dropped into-the well tubing A soas to fall therethrough 'a suitable tool (not shown) may be engagedbeneath the flange l5 to permit lowering. Suitable guide ribs orprojections 25 may be formed on the exterior of the sleeve or body toprevent the cutting blades from hanging or catching on the tubingcouplings or other irregularities and also to aid in guiding thev sameaxially through the tubing during its travel 1 theretlirough. At thestart of the lowering, the

sleeve may be in the position,. shown in Figure 2, but as soon as theblades or the guides strike a projection or accumulation on the wall ofthe tubing bore the frictional engagement of said blades or ribs withsuch projection will cause the sleeve to ride upwardly on the downwardlymoving mandrel, whereby the sleeve, and scraper members l8 and I9carried thereby, are moved to the position shown in Figure 1. In suchposition, the sleeve and members are opposite the cylindrical upperportion of the mandrel, and the lower ends of the members have movedinwardly, whereby the cutting blades l8 and I! are in a retractedposition and the outer diameter of the scraper formed by said blades isreduced to permit fast lowering of the device through the paraffin zone.The lower, outer edges of the blades |8' and I9 are rounded so as toobviate their hanging on the tubing couplings or other irregularities inthe tubing A, as

, IT and the scraper members it and ill thereon,

- escapee wardly so that the outersurfaces of the blades I I and Ill besubstantially flush with the outer 1 wall of the sleeve I! when in aretracted position.

As is well known, parailln usually accumulates near the upper portion 0!the well tubing and ordinarily, it is notnecessary that the device belowered to the bottom of the tubing, it being ,suiiicient that it belowered to a point below the parafiln zone. Any suitable means may beem-. ployed to stop downward movement of the device and in the drawings,a transverse stop pin 25 is disclosed. The pin is located below theparaflin none and extends transversely across the tubing bore;manifestly, when the collar H on the lower end oi the mandrel strikesthe pin, further downward movement of the mandrel is prevented.

As the mandrel strikes the pin it and movement thereof is halted, theweight of the sleeve cause the sleeve to slide downwardly on the mandrelinto engagement with the shoulder it. Such downward sliding of themandrel causes the members it and 19 to be moved radially outwardly, dueto the engagement of the inner surfaces of said members with the flaredor inclined surface ll of the mandrel. Thus, the scraping blades t andit are moved into an expanded or scrap ing position (Figures 2 and 3)and in such position the bottom of each lowerblade it rests on theshoulder It. It is noted in the event that the sleeve ll does not slidedownwardly on the mandrel in by gravity, as explained, the device ismoved upwardly and when the ribs strike a projection or irregularity onthe tubing wall, said sleeve is forced downwardly on the upwardly movingmandrel to expand the blades intomraping position.

The device may be raised to the surface either by the well pressurebelow the same or by a suitable tool (not shown) engaged with theshoulder it on the head it. AS the device moves upwardly, the expandedoverlapping blades and t form a circumferential scraper, which engagesthe accumulation on the wall of the tubing bore, whereby the bore isscraped clean of the accumulation, such as parafiln. The load imposed onthe blades, as they perform the scraping operation is transferred to theshoulder t of rectly on said shoulder, and the upper blades overlie saidlower blades at the ends thereof. With such arrangement, the mandrelrather than the scraping members it and t carries the load.

As the device travels upwardly through the tubing bore, the wall of saidhere is cleaned by the circumferential scraper formed by the scraperblades it and i9. Since the outer expanded diameter of the blades It andit is less than the bore of the tubing, by-pass oi fluid or pressurepast said blades may occur. This well fluid flowing upwardly past theupwardly moving device will tend to keep theupper surfaces of the bladesclean by lifting the paramn, or other accumulation which has beenremoved by the blades. The fluid will now past the device at arelatively high velocity, due to the restricted action.

. v a annular passage and said ffluidis thus directed against theaccumulation, whereby it will tend to remove the paraflin by a cuttingor washing The bore is thus efllciently cleaned upon the upward travelofthe device. when worn,- the scraper members II and I! may be readily.

replaced by merely removing the head it and the sleeve II fromthemandrel ii.

.In Figures l4to 18, a modified form 01' the invention is shown. In thisform, an elongate mandrel-30 has the upper portion of its outer surfacetapered-or inclined at 30' to form an expanding surface. A pluralityofvertical (love tail grooves ll are provided in this: inclined surfaceand extend from the upper end of the mandrel to a point spaced from thelower end thereof. A sleeve 32 surrounds the mandrel and is slidablevertically with relation thereto. A pair of upper arcuate scraper blades33 are adapted to fit within arcuate recesses 34 in the outer surface 01the sleeve and each blade has an inwardly extending arm 35 (Figures 16and 17) which passes through a radial opening it in the sleeve.

The inner end of each arm 35 is dovetailed so as to slidably engagewithinone of the grooves ti of the mandrel.

A pair of lower scraper blades ii are similarly mounted in the sleevebelow the blades ti and in odset relation thereto. Manifestly, when thesleeve moves upwardly on the mandrel, the blades 33 and it areretracted, dueto their inner ends riding within the inclined grooves ti(Figure 14); similarly, downward movement of the sleeve on the mandrelcauses outward movement oi the blades into scraping position (Figures 15and it) Displacement oithe blade arms from the upper ends of the groovesti is prevented by a collar 38 which overhangs the grooves. "l"he collaris made integral with a fishing neck 3% and a depending threaded pin iton said neclr is arranged to be screwed into an opening ill in the upperend oi the mandrel i. -'ll"he operation of this form is the same as thefirst form, the blades 33 and ti being retracted during lowering andexpanded during raising. Retraction and expension of the blades variesthe outside diameter or the circumferential scraper formed -by saidblades, whereby the device may be readily lowered through the paramnnone, and also whereby re-' moval of the accumulation on the wall of thebore is acconiplished when the blades are expended and the deviceraised.

Y the base of the inclined expanding surface l the mandrel since thelower blades it rest diand below said shoulder the mandrel iscylindrical. At the base oil the cylindrical portion, an external flangei2 is provided. A sleeve ill, similar to the sleeve ll, is slidable onthe mandrel and has the scraper members it and it mounted therein in asimilar manner to the mounting of the members in the-sleeve ll. However,the lower end of the sleeve dl does not terminate adjacent the blades itand it but extends therebelow to provide 9. depending skirt portion it,which slides on the outer cylindrical portion of the mandrel,

which portion is below the shoulder dd. The

til

as they perform their scraping operation is trans-v ferred to themandrel 45.

Still another form of the invention is illustrated in Figures 22 to 24,wherein a tapered mandrel 50 is provided. The mandrel has verticalgrooves or channels therein and a pluare slidably mounted on themandrel.

rality of eccentric superimposed scraper rings 52 Each ring has ascraping surface 53 which extends through an arc of more than ninetydegrees and the surfaces 53 are offset radially around the mandrel toform a circumferential scraper. The rings are held in their properrelationship and are guided in their vertical movement, by vertical keysor ribs 54, which are secured to the rings and which engage in thegrooves 5|. The rings are con fined on the mandrel between an enlargedcollar 55 onthe lower end of said-mandrel and a head 56 on the upper endthereof. A sleeve or collar 58, having guide ribs 59, rests on theuppermost ring 52 and its weight holds the rings in engagement with eachother.

may be retracted radially inwardly and when said rings move downwardlyon the mandrel, they are expanded into scraping position. The operation.

' of the illustrated construction may be made, with- 'in the scope ofthe appended claims, without de- 2. A scraping device including, asupport having a projection thereon, and arcuate scraping membersindependently and loosely mounted on the support and freely movableradialiy thereof to an expanded or retracted position, said scrapingmembers coacting with each other to provide continuous circumferentialcutting edges and also coacting with 'the projection on the support,

, whereby the membersare rigidly sustained in an expanded position. i

3; A scraping device including, an axial support having a stationaryinclined portion on its outer surface, a plurality of scrapermembershaving arcuate overlapping scraping faces loosely surrounding thesupport and forming a circumferential scraper, said members being freelyslidable longitudinally of the inclined portion of the support, wherebythe scraping faces are retracted and expanded in a radial direction tovary the outside diameter'of the circumferential scraper.

4.. A scraping device including, an axial support When the rings moveupwardly on the mandrel, their scraping portions 53 having a stationaryinclined portionon its outer surface, a plurality. of scraper membershaving arcuate overlapping scraping faces loosely surrounding thesup'port and formlnga circumferem tial scraper, said member being freelyslidable longitudinally of the inclined portion of the support, meansfor retaining the members in contact with the inclined portion of thesupport,

whereby as the members are moved longitudinally on the support'thescraping faces thereof are retracted or expanded in a radial direction.

5. A scraper including, an axial mandrel having an inclined portion onits outer surface, an annular sleeve surrounding the mandrel and movablethereon, and' a plurality of scraper members carried by the sleeve andhaving arcuate scraping faces, said members being arranged to engage andride upon the inclined portion of the mandrel, whereby when the sleeveis moved on the mandrel, the scraping members are expanded orcontracted.

6. A scraper including, an axial mandrel having an inclined portion onits outer surface, an annular sleeve surrounding ,the mandrel andmovable thereon, and a plurality of scraper members carried by thesleeve and having arcuate scraping faces, the scraper faces of adjacentmembers being located in different horizontal planes and being disposedin overlapping relation so as to form a circumferential scraper, said'members being arranged to engage and ride upon the inclined portion ofthe mandrel, whereby when the sleeve is moved on the mandrel, thescraping members are expanded or contracted.

'7. A scraper including, an axial mandrel having an inclined portion onits outer surface, a sleeve surrounding the mandrel and movablelongitudinally thereof, and a plurality of scraper members mountedwithin the bore of the sleeve and arranged to swing from their upperends and having arcuate scraper faces arranged to be expanded so as toproject beyond the outer surface of the sleeve and coacting with eachother to form a circumferential scraper, the inner surfaces of themembers engaging the inclined portion of the mandrel, whereby themembers are expanded'or retracted radially when the sleeve is movedlongitudinally of the'mandrel.

8. A scraper including, an axial mandrel having an inclined portion onits outer surface, a sleeve surrounding the mandrel and movablelongitudinally thereof, and a plurality of scraper members mountedwithin the bore of the sleeve and arranged to'swing from their upperends and having arcuate scraper faces arranged to be expanded so as toproject beyond the outer surface of the sleeve, the scraper faces ofadjacent members'being located in different horizontal planes and beingdisposed in overlapping relation so as to form a circumferentialscraper, the inner surfaces of the members engaging the inclined portionof the mandrel, whereby the members are expanded or retracted radiallywhen the sleeve is moved longitudinally of the mandrel.

9. A scraper for a tubular element including, a i

support, a scraper assembly on the support and having a plurality ofoverlapping radially movable scraper members mounted to freely movelongitudinally of the support and arranged to be retracted to permit thedevice to be lowered through the tubular element withoutengaging anaccumulation on the wall of the bore thereof, means on the mandrel forexpanding said members whereby as the device moves through the bore saidmembers remove the accumulation, and

means for transferring the load imposed on the members during thescraping operation 'to the s pport so as to relieve the members of suchload. 10. A scraper including, an axial support having a stationaryinclined portion, and a plurality of freely movable scraper memberssurrounding said support and having arcuate overlapping scraping faces,and provided with means co-acting with said inclinedportion whereby theyare retracted and expanded by the inclined portion 0! the support whenmoved longitudinally thereof, said scraping members forming a continuouscircumierent'ial scraper when expanded.

11.A.well scraper including, an axial support adapted to be lowered intoa well pipe having an accumulation in its bore, and a plurality of radially movable scraping members having arcuate overlapping scraping facesdisposed to remove said accumulation when the support is moved upwardlytherethrough, said scraping members being so loosely and freely mountedon said support as to be readily moved radially inward by saidaccumulation to reduce the diameter or the scraper when the support ismoved downwardly HERBERT C. OTIS.

. therethrough.

